1.Field of the Invention
The present invention generally relates to a combined skirt-reefing and slider method for controlled parachute opening.
2.Description of the Related Art
An important and desirable operating capability in a parachute system is the ability to control the opening of the parachute so as to decrease its opening force. Such an operating capability provides for controlled and safe airdrops thereby protecting personnel and cargo. This aforesaid operating capability is particularly important for current precision airdrop systems that deploy parachutes at an altitude of about 25,000 feet. At this high altitude, the true aircraft speed is high as 200 knots (as compared to 130 knots near sea level). This relatively high aircraft speed results in extremely high opening forces if the parachute is not inflated in a controlled manner to decrease the peak opening force.
Parafoils (gliding ram-air inflated parachutes) are currently used to implement precision airdrops. In some instances, sliders are used on the parafoils to control the opening of the parafoil. However, the relatively high cost of parafoils prohibits the use of parafoils on a large scale. Other types of parachute systems used today include low cost, standard round cargo parachutes that are not designed for high altitude deployment. Skirt reefing techniques are commonly used to control the opening of round parachutes. These skirt reefing techniques typically use reefing lines in conjunction with pyrotechnic cutters. Other prior art techniques for controlling the canopy opening process use loose sliders. However, these aforesaid prior art techniques do not sufficiently address unacceptably high opening forces that jeopardize the structural integrity of both the canopy fabric and suspension lines.
What is needed is a cargo parachute system having a skirt reefing system that sufficiently reduces the opening forces and which is relatively more economical to implement in comparison to prior art cargo parachute reefing systems.